Gauging device



y 5, 1942- H. J. ASHLOCK 2,281,907

GAUGING DEVICE Filed Jan. 11, 1940 2 Sheets-Sheet 1 y 1942- H. J. ASI-ILOCK 2,281,907

' GAUGING DEVICE Filed Jan. 11, 19 10 2 sheets sheet 2 FIG-2 I 1 II IIIn l III-III Patented May 5, 1942 UNiTED STATES PATENT OFFICE GAUGINGDEVICE Application January 11, 1940, Serial No. 313,398

1 Claim.

The present invention relates to a system for gauging liquid reservoirs,and more particularly a system for gauging liquid reservoirs in which toprevent evaporation losses the contents are held under super-atmosphericpressures.

It is an object of the invention to provide an apparatus for makingliquid level measurements at atmospheric pressure of a liquid body heldunder greater or less than atmospheric pressure. It is also an object ofthe invention to provide a convenient means for gauging spheroidaltanks.

The invention and its objects may be fully understood from the followingspecification, when it is read in conjunction with the accompanyingdrawings in which Fig. 1 is a diagrammatic view of a section of aspheroidal tank;

Fig. 2 is a side elevation of a portion of the structure, enlarged andpartly in section; and

Fig. 3 is a side elevation of another portion of the structure, enlargedand partly in section.

Referring to the drawings, the numeral I designates a spheroidal tank ofgenerally conventional design in which has been included a gaugingcolumn 2 and its required equipment and pipe connections.

The column 2 may be a single or built-up length of standard steel pipeextending through a convenient opening in the highest portion of thetank, and supported therein by means of the frame support 3, whichshould be rigidly secured to the tank bottom by any suitable means.Preferably the bottom end of the pipe should be so supported as to beslightly above the maintained level of water in the tank. The upper endof the pipe column 2 extends through a flanged opening 4 in the upperwall, terminating a short distance thereabove. At a point adjacent theend, a collar 5 is welded to the pipe, and the collar 5 is flexiblyjoined to a flange 6, about opening 4, by means of a bellows orcorrugated expansion joint member 1 secured in fluid-tight relation toboth the collar and flange, as by bolts 8. The extreme and open end ofthe column 2 is capped by means of a gate valve 9, the lower flangedport of which is .joined to the flanged column end, while the upperflanged port is joined to a hatch member Ill having a substantiallyfluid-tight cover II.

The column 2 at its upper end is in restricted communication with theinterior of the spheroid I by way of the pipe connection 12, joined tothe column at a point intermediate the collar member 5 and the flangedend of the column, and to the tank at l3. The valve [4 provides forblocking the line as required in the operation later described, whilevalve l5 when open permits equalization of any pressure in the columnwith that of the surrounding atmosphere. This line should be providedwith a flexible or movable joint as at lZa.

Within the tank I, a suitable frame support or box frame structure 3 isdisposed about the column 2 supporting it rigidly within the tank. Fromthe bottom of the column, a line l6 extends radially across the tank inan inclined plane, passing through the tank wall at H at substantiallythe lower level of the tank contents maintained above the water therein.At a point [8, slightly above the line IS, a draw-off line I!) isextended through the tank wall, opening thereinto, and connected at itsouter end by means of line 20, to the outer end of the line I6. Suitablevalves Zl, 22 and 23 are disposed in the respective pipe connections asshown. It is also desirable that the line l6 be provided with a flexibleor swing joint as at 5a.

In operation, the valve I5 in the line I2 is closed, and valve l4opened. At the same time, with valve 23 closed, valves 2| and 22 areopened, permitting the liquid within the tank to flow through lines I9,20 and 16 into the lower part of the column 2. As pressure in the tankand column are equalized through the line l2, the liquid entering thecolumn through line I6, will establish a level therein equivalent to thelevel of liquid in the tank. When the level of liquid has beenestablished in the column, the valves I4, 21 and 22 are closed, and thevalve I5 opened to vent the column to the atmosphere. With the column atatmospheric pressure, the gate valve 9 and hatch m are opened, and byany conventional means, the level of the liquid in the column may bedetermined. Of course, the liquid level in the column will be equivalentto that of the body of liquid in the tank. Such flashing of the liquidas might be expected to be occasioned by a reduction of pressure on thecolumn, will have no noticeable effect in reducing the liquid level, due

to the small area of the liquid exposed, and the length of the liquidcolumn.

When the liquid level has been gauged, the column may be sealed from theatmosphere and returned to communication with the interior of the tank.It is not necessary to drain the column unless desired, or when the tankis to be changed over to the storage of a dissimilar liquid. In suchinstance, the valves 2| and 23 may be opened before closing the valve[5, and the contents of the column led off through suitable pipeconnections.

Of course, the use of the system disclosed is not limited to use underthe pressure conditions set forth, and may also find application toordinary tanks to reduce evaporation loss by exposure of large areas ofliquid to air currents during a gauging operation. It is contemplatedthat numerous modifications and changes may be made with respect to theapparatus as described and illustrated, Without departing from theconcept of the invention disclosed. It is not intended, therefore, thatthe invention shall be restricted in any Way by the description or thedrawings, which have been set forth for the purpose of illustration anda better understanding of the invention, but only by the appended claim.

I claim:

In a spheroidal storage tank for liquids held under greater thanatmospheric pressure, a liquid level gauging apparatus for making liquidlevel measurements at atmospheric pressure comprising a tubular columnextending vertically of said tank through the upper portion of the roofthereof and terminating above the bottom of the tank, a corrugatedtubular expansion member connecting the column to the roof, a conduit incommunication with the lower end of said column extending in adownwardly inclined plane substantially horizontally therefrom through aside Wall of the tank, a second conduit communicating through said Wallwith the interior of the tank adjacent the lower level of liquid in thetank, a valved pipe connection between said conduits to control theinlet of liquid from the tank to the column, a valved flexible pipeconnection between the upper end of the column above the expansionmember and the interior of the tank, above the liquid therein, valvemeans for venting said column to the atmosphere, the valves when openpermitting the liquid Within the tank to flow into the column to a levelequivalent to the level in the tank, and a closure for the upper end ofsaid column giving access thereto for gauging the level of liquidtherein when the valves are closed.

HAROLD J. ASHLOCK.

